Stadium: Court 1 Round: 62 Ground: Hardcourt outdoor
| ITF M25 Quinta Do Lago | 2023/03/09 17:20 | Jesper De Jong v Guy Den Heijer | 6-3,6-1 |
| ITF M25 Quinta Do Lago | 2023/03/09 13:30 | Sean Hodkin v Guy Den Heijer | 4-6,4-6 |
| ITF M25 Quinta Do Lago | 2023/03/08 16:15 | Luis Miguel Saraiva v Guy Den Heijer | 4-6,3-6 |
| ITF M25 Loule | 2023/02/26 10:00 | Timofey Stepanov v Guy Den Heijer | 6-4,6-2 |
| ITF M25 Faro | 2023/02/21 10:00 | Francois Musitelli v Guy Den Heijer | 6-7,7-6,12-10 |
| ITF M25 Faro | 2023/02/20 10:00 | Guy Den Heijer v Ryotaro Matsumura | 6-4,4-6,10-3 |
| ITF M25 Faro | 2023/02/19 10:00 | Guy Den Heijer v Stepan Pecak | 6-3,6-7,12-10 |
| ITF M25 Al Zahra | 2023/01/25 13:20 | Guy Den Heijer v Prajnesh Gunneswaran | 1-6,6-7 |